Relay.



PATENTED AUG. 20, 1907.

J. B. STRUBLE.

RELAY. APPLICATION rum) rm. 16,1607.

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mi Q n 1 INVENTOI? W/T NE 88158 A; ATTORNEY PATENTED AUG. 20, 1907.

J. B. STRUBLB.

RELAY. APPLICATION FILED FEB. 18, 1907.

2 SHEETS-SHEET 2.

INVENTOH via ATTORNEY QZKW' 712 UNITED STATES PATENT orrros.

JACOB B. STRUBLE, OF WILKINSBURG, PENNSYIJVANIA, ASSIGNOR TO THE UNION SWITCH AND SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA. A CORPORATION OF PENN- SYLVANIA.

' RELAY.

Specification of Letters Patent.

Patented Aug. 20, 1907.

Application filed February 18,1907. Serial No. 357.919.

To all whom it may concern:

Be it known that I, JACOB B. STRUBLE, a citizen of the United States, residing at Wilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Relays, of which the following is a specification.

My invention relates to relays, and especially to relays for use in railway signaling systems employing alternating current track circuits, whether such systems are used on steam railways or on electric railways, wherein the track rails are included in the return path to the generator for the car propulsion current which maybe either direct or alternating.. Y

I will describe a relay embodying my invention and its use in a signaling system for electric railways, the track rails of which are included in the return path for the car propulsion current.

In the accompanying drawings, Figure 1 is a vertical sectional view of a relay embodying my invention.

Fig. 2 is another vertical sectional view of the relay illustrated in Fig. I. Fig. 3 is a diagiammatical view of a portion of an electric railway, the track rails of which are divided to form block sections and are ineluded in the return path for the car propulsion current and having applied thereto an alternating current signaling system embodying my invention.

Similar letters of reference designate corresponding parts in all of the tigures.- v v R designates a relay. As here shown it comprises a core 1', which is substantially W-shaped, an energizing winding r surrounding the middle leg 1 of the core, and an arn'iature r'-, which is pivoted intermediate its ends upon the middle leg oi the core. i

r r designate the outside legs of the core, the end portions of which form poles.

The core 1' and armature are laminated, and the armature r" is made comparatively heavy in order that it will not be vibrated or chatter on its pivots by the alternating flux in the core due to an alternating cur- 40 rent traversing the energizing coil. The armature 1' is provided with a rect angular opening to receive the middle leg of the core, and this opening is of such size as to provide the same air space between each of the four" walls of the opening and the core of equal dimensions.

The purpose of this arrangement is to avoid the vibration oi the armature due to the passage of alternating lines of force from the middle leg to the armature. It

drill be evident that the pull exerted by these lines of force is equal in all directions and hence it is neutralized. The pivots for the armature are here shown as being adjustable screws r" the pointed ends of which enter tum-magnetic (copper) bushing or bushings 1" provided in the middle leg 1 of the core.

1*" designates a counterweight for the armature which tends always to tilt or rock the armature on its pivots through the legs r T and the armature.

pulsion frequency) traverses the winding 2'.

in a direction to disengage or open the contacts con-' trolled thereby.

r designates a closed conductor (which may be in the form of a copper ferrule) surrounding the'leg T and r,

r, pole pins of some non-magnetic material, for exam- 6O ple, bone or brass, secured in the end faces of the legs 1", T The purpose of these pins is to regulate the amount of air gap between the armature and end faces of the legs 1", 1*, and to prevent the armature from sticking, for any cause, to the end faces of the legs 1", T The pole pin r projects beyond the end face of the leg 1' a greater distance than does the pole pin r from the end face of the leg 7*, thereby providing a longer air gap between the end face of the leg r and the armature r'-, than between the end face of the leg r and the armature r-. The difierence between the two air gaps is equivalent in reluctance, to the reluctance offered by the closed conductor r with a low frequency current. The movements of the armature r on its pivots opens and closes contacts in one or more circuits.

r designates a suitable frame suitably pivoted to a framework provided for the parts of the relay. The frame r carries one or more contact springs 7', which are insulated from each other and the frame. The end of the armature r is connected by a link r with the frame so that as the armature moves the frame 1 moves Q with it.

r designates fixed contacts carried by a top 1' for a suitable casing which receives the several parts comprised in the relay. i

The operation of the relay is as follows: The flux produced by an alternating current traversing the winding r will have two paths in the core and armature; one path will be through the middle leg, the armature and the log T and the other through the middle leg, 9 0 the armature and leg 1"". The position of the armature with relation to the end faces of the legs 7", r will be dependent upon the relative amount of fiux' passing In practice, the closed conductor r and the air gaps between the armature and the legs r 7 are so proportioned that the armature will be balanced or will be attracted to the leg 1 when an alternating current of 25 cycles (pro- Consequently, the relay in a signaling system applied to an electric railway using an alternating current of 25 cycles or less for car propulsion current will not respond to the alternating propulsion current to close the signal circuit. I may state here, that when the armature is tilted on its pivot so that one end contacts with the pole l0 5 pin T7, the contacts 7 1' are disengaged or opened. They will also be disengaged or opened when the armature is balanced on its pivots. The contacts r T are only engaged or closed when the armature is at- V tracted to leg 1 1 10 As is well known, the closed conductor T will pro.- duce a counter-flux when out by flux-due to a current traversing the winding r and this counter-flux at 25 cycles may be considered the equivalent of the reluctance caused by the excess air gap of leg 1 Con sequently, the effect on the armature due to the 25 cycle current is neutralized or tends to cause a movement of the armature toward leg 1". If an alternating current of high frequency, (say 60 cycles) is traversing the winding 1', the closed conductor 1* will offer a greater counter-flux than if an alternating current of lower frequency, (say 25 cycles) was traversing the winding T and the pole of the leg r will be proportionally stronger. If now the alternating signaling current is of a high frequency, the armature will always be moved toward the leg 1 to engage or close the contacts r r Of course, when the alternating signaling current is short circuited from the coil the armature will be moved by the counter-Weight r to disengage or open the contacts r", 1 i g Referring now to Fig. 3, A designates a portion of an electric railway, which is divided by insulated joints to form block sections. As shown, both rails are provided with insulated joints to form block sections, though, if desired, only one such railway'may be so divided. Both arrangements are well-known in the art. In the drawings I have shown one block section and portions of two others.

As the rails (one 'or both) are to be included in the return path for the car propulsion current, which, for the purpose of this invention should be alternating and of a low frequency, provision is made for conducting the propulsion current around insulation points by means of reactance bonds.

In the drawings I have diagrammatically illustrated what is known in the art as the balance type of reactance bond.

B, B, B B etc. designate such bonds. The e bonds, as is well known conrpriso :tcorc, a winding or windings all the turns of which are in the same direction and in close inductive relation. Such a type of bond is illustrated in U. S. Patcut No. 838 916. granted December 18th, 1906. In this type of bond the propulsion current is made to flow through two equal parts of the winding or two windings of the same number of turns in reverse directions so that the propulsion current produces no magnetizing effect. on the core of the bond. As shown, the windings of two adjacent bonds are connected by a conductor b or there maybe a plurality of such conductors. By this arrangement of track the propulsion current in its return through the rails and the windings in the manner stated will not magnetize the cores of the reactance bonds, thus leaving them free to act as impedances. for the alternating signaling current. which is of a higher frequency than the, car propulsion current. i

I have not illustrated the generator for the carpropulsion current or the trolley or third rail. as these are well known in the art, and it may be either a direct or an alternating current generator.

The signaling system applied to the railway comprises a railway signal or signals for each block section,

and a track circuit for each block section to control one operation of the railway signal or signals. S designates one such railway'signal.

I Each track circuit comprises a' source of alternating current and a relays The source of alternating current to the track circuit of each block section is in the form of a transformer T, the secondary of which is connected with the track rails of the block section, while the primarythereof may be in multiple circuit with mains 20, 21, extending along the track from the generator G. If the signaling system is applied to an electric railroad f cuit for the alternating signaling current. and the winding 1 of the relay being thus denergized, the armature T will move to open the contacts in the signal circuit and allow the railway signal to indicate that fact. When the train or car moves out of the block section the parts are restored to the position shown. Should the propulsion current (if it be alternating) for any reason be caused to flow through the winding of the relay with the signaling current absent therefrom, it will not cause the armature to move to close the signal current for the reasons hereinbeiore stated. Should the car propulsion current be direct and the armature be in contact with the pole of the legs r it will be held in that position owing to there being less air gap at that point than 1 between the armature and leg 1'. If on the other hand direct car propulsion current traverse the winding l. A relay comprising a core affording two magnetic paths. an energizing winding for said core. a pivoted armature for said core. and means fol-increasing the reluctance of one magnetic path over the other, whereby the.

armature will he moved on its pivot in response 'to the strongest magnetic circuit.

2. A relay comprising a W-shaped core, an armature pivoted to the middle leg of the core, an energizing winding for said core, and a closed conductor surrounding one leg of said core.

A relay comprising a substantially W-shaped core. an armature pivoted to the middle leg of said core, pole pins in the outside legs of the core for producim. different size air gaps between the armature and the outside legs, an energizing winding for the core. and a closed conductor on one leg of the core.

In testimony whereof I have signed my name to this specification in the presence of two subscribed witnesses.

JACOB B. STRUBLE.

Witnesses i .T. G. Scnununnn,

W. L. MfDANII'lL. 

